Using get-view, how to get guest VMs on a vmhost or in a cluster/datacenter, when the parents were also retrieved via get-view

[lanwench]

Hi LucD et al.  -

In my functions, I am trying whenever possible to substitute get-view for get-vm (and get-vmhost, get-cluster, get-datacenter, etc.), because it's soooo much faster.

I still can't figure out the equivalent to:

$ get-vmhost | get-vm

For example, if I have a vmhost object retrieved via get-view, how do I pipe that (or otherwise reference it) to get all the guests on that host?

$ Get-View -ViewType HostSystem -Filter @{Name="hostname.domain.local"}  | get-view -ViewType VirtualMachine  # this does not work, obviously

(and yes, I'd add -Property once I figured out which properties I need )

I'm on 6.5.0.2, if that makes any difference.

Thanks!

Paula

[LucD · Accepted solution]

One way is using the SearchRoot parameter.

Like this for example

$esxName = 'esx1'

$esx = Get-View -ViewType HostSystem -Property Name -Filter @{'Name'=$esxName}

$vm = Get-View -ViewType VirtualMachine -SearchRoot $esx.MoRef

$vm | select Name

But the easiest one is like this imho

$esxName = 'esx1'

$esx = Get-View -ViewType HostSystem -Filter @{'Name'=$esxName}

Get-View -Id $esx.Vm

[lanwench]

Thanks as always, Luc.

I think the first approach will work best for me. I have to fiddle around with properties to make sure I'm filtering out as much as possible for speed.

I like the simplicity of the 2nd approach but it seems like it might make it more expensive to look for all guests in a cluster or datacenter, right? Wouldn't I have to do something like the following?

$ClusterObj = Get-View -ViewType ClusterComputeResource -Filter @{Name = "^$Cluster"}
$VMObj = Get-View -id (Get-View -ID $ClusterObj.Host).VM

pk

[LucD]

Correct, if you want to that for a cluster, you would have to first get all the ESXi member nodes, and then for each ESXi node the VMs.

But I suspect, vSphere does something similar behind the covers.

The difference could be in the overhead, if any, that the additional Get-View introduces.

The only way to know, would be to time with Measure-Command.

But then again, you would need to be running against a very big environment before seeing any significant differences in execution time I assume.